It has the same name, the same look and the same price - but this one's legal.

While police around the country were busy checking store shelves yesterday for K2, Hamilton dairies were busy stocking its replacement. The Temporary Class Drug Notice, which started at midnight, makes it illegal to import, manufacture, sell or supply BB-22 and 5F-AKB48 - found in K2. The new product, which hit Hamilton stores yesterday, is essentially the same product without the two chemicals.

Waikato Police district commander Superintendent Win van der Velde said he wasn't aware of the new K2, but said it didn't surprise him that it had already hit stores.

"For me, in the nicest possible way, this is about responsible shop owners reflecting that responsibility with the products they sell and these types of synthetic cannabanoids, where their harmfulness has not been accurately assessed. The sale of that to me is a risk and shop owners need to take some ownership for that as much as the manufacturers of the product."

A Waikato Times investigation to uncover whether stores were flouting the K2 ban took an unexpected twist when it was found that some stores were already stocking a new version of the controversial legal high.

"This product is fully compliant as of 9th May 2013," a sticker on the new K2 packet says.

Mr van der Velde said he expects a steady stream of alternatives to start hitting store shelves. "The availability of synthetic drugs is huge and hence the need for the legislation."